From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 67BF42571 for ; Mon, 13 Mar 2023 12:48:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24088C4339C; Mon, 13 Mar 2023 12:48:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678711734; bh=CMYI7NCjXkkq8RKyRgm82qexoeOMACscNwYRQyYIBGw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QSn2+FAWlYC9p2zbv40Q9zTVKKIXe32rbGiEJq9r4XDds6l0KHRM5TUmCxq576ezT XCpx6bESHcTWZoFPDGw8P93RJK6+z64Bount5aFktO2jrlzdySsKjjV9l3ZQG4Lylj tcDHhPvkrbKPUFpK1OIX5VxCwuXPaE1/U1Lvq+1B2SQDjO9MH4n3Qhxr/eCvYBSbvV iFUOeElbMf/oivQkEfSEtM4Bq7aeE6DkuovYZmTtNrtU2M3GW5Un6tmu0x30gLwhKJ mc6Qt7Rcsm1Gz9MjO4x2DKXJYeh+21iB0qkM4BRTb6iESGsD9CbLPd4cEvbHC2ctkO gOYk2l+zspeiQ== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1pbhbg-00HEdE-0C; Mon, 13 Mar 2023 12:48:52 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Ricardo Koller , Simon Veith , Reiji Watanabe , Colton Lewis , Joey Gouly , dwmw2@infradead.org Subject: [PATCH v2 02/19] KVM: arm64: timers: Use a per-vcpu, per-timer accumulator for fractional ns Date: Mon, 13 Mar 2023 12:48:20 +0000 Message-Id: <20230313124837.2264882-3-maz@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230313124837.2264882-1-maz@kernel.org> References: <20230313124837.2264882-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, ricarkol@google.com, sveith@amazon.de, reijiw@google.com, coltonlewis@google.com, joey.gouly@arm.com, dwmw2@infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Instead of accumulating the fractional ns value generated every time we compute a ns delta in a global variable, use a per-vcpu, per-timer variable. This keeps the fractional ns local to the timer instead of contributing to any odd, unrelated timer. Signed-off-by: Marc Zyngier --- arch/arm64/kvm/arch_timer.c | 2 +- include/kvm/arm_arch_timer.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c index e1af4301b913..9515c645f03d 100644 --- a/arch/arm64/kvm/arch_timer.c +++ b/arch/arm64/kvm/arch_timer.c @@ -212,7 +212,7 @@ static u64 kvm_counter_compute_delta(struct arch_timer_context *timer_ctx, ns = cyclecounter_cyc2ns(timecounter->cc, val - now, timecounter->mask, - &timecounter->frac); + &timer_ctx->ns_frac); return ns; } diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h index c52a6e6839da..70d47c4adc6a 100644 --- a/include/kvm/arm_arch_timer.h +++ b/include/kvm/arm_arch_timer.h @@ -44,6 +44,7 @@ struct arch_timer_context { /* Emulated Timer (may be unused) */ struct hrtimer hrtimer; + u64 ns_frac; /* Offset for this counter/timer */ struct arch_timer_offset offset; -- 2.34.1